]>
Commit | Line | Data |
---|---|---|
340a614a HD |
1 | /* |
2 | * OMAP mailbox driver | |
3 | * | |
f48cca87 | 4 | * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved. |
340a614a | 5 | * |
f48cca87 | 6 | * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com> |
340a614a HD |
7 | * |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License | |
10 | * version 2 as published by the Free Software Foundation. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, but | |
13 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA | |
20 | * 02110-1301 USA | |
21 | * | |
22 | */ | |
23 | ||
340a614a | 24 | #include <linux/interrupt.h> |
b3e69146 FC |
25 | #include <linux/spinlock.h> |
26 | #include <linux/mutex.h> | |
340a614a | 27 | #include <linux/delay.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
b5bebe41 OBC |
29 | #include <linux/kfifo.h> |
30 | #include <linux/err.h> | |
58256307 | 31 | #include <linux/notifier.h> |
8dff0fa5 | 32 | |
ce491cf8 | 33 | #include <plat/mailbox.h> |
340a614a | 34 | |
9c80c8cd | 35 | static struct omap_mbox **mboxes; |
340a614a | 36 | |
5f00ec64 | 37 | static int mbox_configured; |
72b917ef | 38 | static DEFINE_MUTEX(mbox_configured_lock); |
5f00ec64 | 39 | |
b5bebe41 OBC |
40 | static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE; |
41 | module_param(mbox_kfifo_size, uint, S_IRUGO); | |
42 | MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)"); | |
43 | ||
9ae0ee00 HD |
44 | /* Mailbox FIFO handle functions */ |
45 | static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox) | |
46 | { | |
47 | return mbox->ops->fifo_read(mbox); | |
48 | } | |
49 | static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg) | |
50 | { | |
51 | mbox->ops->fifo_write(mbox, msg); | |
52 | } | |
53 | static inline int mbox_fifo_empty(struct omap_mbox *mbox) | |
54 | { | |
55 | return mbox->ops->fifo_empty(mbox); | |
56 | } | |
57 | static inline int mbox_fifo_full(struct omap_mbox *mbox) | |
58 | { | |
59 | return mbox->ops->fifo_full(mbox); | |
60 | } | |
61 | ||
62 | /* Mailbox IRQ handle functions */ | |
9ae0ee00 HD |
63 | static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) |
64 | { | |
65 | if (mbox->ops->ack_irq) | |
66 | mbox->ops->ack_irq(mbox, irq); | |
67 | } | |
68 | static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) | |
69 | { | |
70 | return mbox->ops->is_irq(mbox, irq); | |
71 | } | |
72 | ||
340a614a HD |
73 | /* |
74 | * message sender | |
75 | */ | |
b5bebe41 | 76 | static int __mbox_poll_for_space(struct omap_mbox *mbox) |
340a614a HD |
77 | { |
78 | int ret = 0, i = 1000; | |
79 | ||
80 | while (mbox_fifo_full(mbox)) { | |
81 | if (mbox->ops->type == OMAP_MBOX_TYPE2) | |
82 | return -1; | |
83 | if (--i == 0) | |
84 | return -1; | |
85 | udelay(1); | |
86 | } | |
340a614a HD |
87 | return ret; |
88 | } | |
89 | ||
b2b6362e | 90 | int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg) |
340a614a | 91 | { |
b5bebe41 OBC |
92 | struct omap_mbox_queue *mq = mbox->txq; |
93 | int ret = 0, len; | |
5ed8d32e | 94 | |
a42743c2 | 95 | spin_lock_bh(&mq->lock); |
ec24751a | 96 | |
b5bebe41 OBC |
97 | if (kfifo_avail(&mq->fifo) < sizeof(msg)) { |
98 | ret = -ENOMEM; | |
99 | goto out; | |
100 | } | |
101 | ||
a42743c2 KH |
102 | if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) { |
103 | mbox_fifo_write(mbox, msg); | |
104 | goto out; | |
105 | } | |
106 | ||
b5bebe41 OBC |
107 | len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); |
108 | WARN_ON(len != sizeof(msg)); | |
340a614a | 109 | |
5ed8d32e | 110 | tasklet_schedule(&mbox->txq->tasklet); |
340a614a | 111 | |
b5bebe41 | 112 | out: |
a42743c2 | 113 | spin_unlock_bh(&mq->lock); |
b5bebe41 | 114 | return ret; |
340a614a HD |
115 | } |
116 | EXPORT_SYMBOL(omap_mbox_msg_send); | |
117 | ||
5ed8d32e | 118 | static void mbox_tx_tasklet(unsigned long tx_data) |
340a614a | 119 | { |
5ed8d32e | 120 | struct omap_mbox *mbox = (struct omap_mbox *)tx_data; |
b5bebe41 OBC |
121 | struct omap_mbox_queue *mq = mbox->txq; |
122 | mbox_msg_t msg; | |
123 | int ret; | |
340a614a | 124 | |
b5bebe41 OBC |
125 | while (kfifo_len(&mq->fifo)) { |
126 | if (__mbox_poll_for_space(mbox)) { | |
eb18858e | 127 | omap_mbox_enable_irq(mbox, IRQ_TX); |
b5bebe41 | 128 | break; |
340a614a | 129 | } |
b5bebe41 OBC |
130 | |
131 | ret = kfifo_out(&mq->fifo, (unsigned char *)&msg, | |
132 | sizeof(msg)); | |
133 | WARN_ON(ret != sizeof(msg)); | |
134 | ||
135 | mbox_fifo_write(mbox, msg); | |
340a614a HD |
136 | } |
137 | } | |
138 | ||
139 | /* | |
140 | * Message receiver(workqueue) | |
141 | */ | |
142 | static void mbox_rx_work(struct work_struct *work) | |
143 | { | |
144 | struct omap_mbox_queue *mq = | |
145 | container_of(work, struct omap_mbox_queue, work); | |
340a614a | 146 | mbox_msg_t msg; |
b5bebe41 OBC |
147 | int len; |
148 | ||
149 | while (kfifo_len(&mq->fifo) >= sizeof(msg)) { | |
150 | len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); | |
151 | WARN_ON(len != sizeof(msg)); | |
340a614a | 152 | |
58256307 KH |
153 | blocking_notifier_call_chain(&mq->mbox->notifier, len, |
154 | (void *)msg); | |
d2295042 FGL |
155 | spin_lock_irq(&mq->lock); |
156 | if (mq->full) { | |
157 | mq->full = false; | |
158 | omap_mbox_enable_irq(mq->mbox, IRQ_RX); | |
159 | } | |
160 | spin_unlock_irq(&mq->lock); | |
340a614a HD |
161 | } |
162 | } | |
163 | ||
164 | /* | |
165 | * Mailbox interrupt handler | |
166 | */ | |
340a614a HD |
167 | static void __mbox_tx_interrupt(struct omap_mbox *mbox) |
168 | { | |
eb18858e | 169 | omap_mbox_disable_irq(mbox, IRQ_TX); |
340a614a | 170 | ack_mbox_irq(mbox, IRQ_TX); |
5ed8d32e | 171 | tasklet_schedule(&mbox->txq->tasklet); |
340a614a HD |
172 | } |
173 | ||
174 | static void __mbox_rx_interrupt(struct omap_mbox *mbox) | |
175 | { | |
b5bebe41 | 176 | struct omap_mbox_queue *mq = mbox->rxq; |
340a614a | 177 | mbox_msg_t msg; |
b5bebe41 | 178 | int len; |
340a614a | 179 | |
340a614a | 180 | while (!mbox_fifo_empty(mbox)) { |
b5bebe41 | 181 | if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) { |
1ea5d6d1 | 182 | omap_mbox_disable_irq(mbox, IRQ_RX); |
d2295042 | 183 | mq->full = true; |
340a614a | 184 | goto nomem; |
1ea5d6d1 | 185 | } |
340a614a HD |
186 | |
187 | msg = mbox_fifo_read(mbox); | |
340a614a | 188 | |
b5bebe41 OBC |
189 | len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); |
190 | WARN_ON(len != sizeof(msg)); | |
340a614a | 191 | |
340a614a HD |
192 | if (mbox->ops->type == OMAP_MBOX_TYPE1) |
193 | break; | |
194 | } | |
195 | ||
196 | /* no more messages in the fifo. clear IRQ source. */ | |
197 | ack_mbox_irq(mbox, IRQ_RX); | |
f48cca87 | 198 | nomem: |
c4873005 | 199 | schedule_work(&mbox->rxq->work); |
340a614a HD |
200 | } |
201 | ||
202 | static irqreturn_t mbox_interrupt(int irq, void *p) | |
203 | { | |
2a7057e3 | 204 | struct omap_mbox *mbox = p; |
340a614a HD |
205 | |
206 | if (is_mbox_irq(mbox, IRQ_TX)) | |
207 | __mbox_tx_interrupt(mbox); | |
208 | ||
209 | if (is_mbox_irq(mbox, IRQ_RX)) | |
210 | __mbox_rx_interrupt(mbox); | |
211 | ||
212 | return IRQ_HANDLED; | |
213 | } | |
214 | ||
340a614a | 215 | static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, |
5ed8d32e S |
216 | void (*work) (struct work_struct *), |
217 | void (*tasklet)(unsigned long)) | |
340a614a | 218 | { |
340a614a HD |
219 | struct omap_mbox_queue *mq; |
220 | ||
221 | mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL); | |
222 | if (!mq) | |
223 | return NULL; | |
224 | ||
225 | spin_lock_init(&mq->lock); | |
226 | ||
b5bebe41 | 227 | if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL)) |
340a614a | 228 | goto error; |
340a614a | 229 | |
5ed8d32e S |
230 | if (work) |
231 | INIT_WORK(&mq->work, work); | |
340a614a | 232 | |
5ed8d32e S |
233 | if (tasklet) |
234 | tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox); | |
340a614a HD |
235 | return mq; |
236 | error: | |
237 | kfree(mq); | |
238 | return NULL; | |
239 | } | |
240 | ||
241 | static void mbox_queue_free(struct omap_mbox_queue *q) | |
242 | { | |
b5bebe41 | 243 | kfifo_free(&q->fifo); |
340a614a HD |
244 | kfree(q); |
245 | } | |
246 | ||
c7c158e5 | 247 | static int omap_mbox_startup(struct omap_mbox *mbox) |
340a614a | 248 | { |
5f00ec64 | 249 | int ret = 0; |
340a614a HD |
250 | struct omap_mbox_queue *mq; |
251 | ||
58256307 KH |
252 | mutex_lock(&mbox_configured_lock); |
253 | if (!mbox_configured++) { | |
254 | if (likely(mbox->ops->startup)) { | |
5f00ec64 | 255 | ret = mbox->ops->startup(mbox); |
58256307 KH |
256 | if (unlikely(ret)) |
257 | goto fail_startup; | |
258 | } else | |
259 | goto fail_startup; | |
340a614a HD |
260 | } |
261 | ||
58256307 KH |
262 | if (!mbox->use_count++) { |
263 | ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, | |
264 | mbox->name, mbox); | |
265 | if (unlikely(ret)) { | |
266 | pr_err("failed to register mailbox interrupt:%d\n", | |
267 | ret); | |
268 | goto fail_request_irq; | |
269 | } | |
270 | mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet); | |
271 | if (!mq) { | |
272 | ret = -ENOMEM; | |
273 | goto fail_alloc_txq; | |
274 | } | |
275 | mbox->txq = mq; | |
340a614a | 276 | |
58256307 KH |
277 | mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL); |
278 | if (!mq) { | |
279 | ret = -ENOMEM; | |
280 | goto fail_alloc_rxq; | |
281 | } | |
282 | mbox->rxq = mq; | |
283 | mq->mbox = mbox; | |
340a614a | 284 | } |
58256307 | 285 | mutex_unlock(&mbox_configured_lock); |
340a614a HD |
286 | return 0; |
287 | ||
ab66ac30 | 288 | fail_alloc_rxq: |
340a614a | 289 | mbox_queue_free(mbox->txq); |
ab66ac30 | 290 | fail_alloc_txq: |
340a614a | 291 | free_irq(mbox->irq, mbox); |
ab66ac30 | 292 | fail_request_irq: |
01072d8f | 293 | if (mbox->ops->shutdown) |
340a614a | 294 | mbox->ops->shutdown(mbox); |
58256307 KH |
295 | mbox->use_count--; |
296 | fail_startup: | |
297 | mbox_configured--; | |
298 | mutex_unlock(&mbox_configured_lock); | |
340a614a HD |
299 | return ret; |
300 | } | |
301 | ||
302 | static void omap_mbox_fini(struct omap_mbox *mbox) | |
303 | { | |
58256307 KH |
304 | mutex_lock(&mbox_configured_lock); |
305 | ||
306 | if (!--mbox->use_count) { | |
307 | free_irq(mbox->irq, mbox); | |
308 | tasklet_kill(&mbox->txq->tasklet); | |
c4873005 | 309 | flush_work_sync(&mbox->rxq->work); |
58256307 KH |
310 | mbox_queue_free(mbox->txq); |
311 | mbox_queue_free(mbox->rxq); | |
312 | } | |
340a614a | 313 | |
58256307 KH |
314 | if (likely(mbox->ops->shutdown)) { |
315 | if (!--mbox_configured) | |
5f00ec64 | 316 | mbox->ops->shutdown(mbox); |
5f00ec64 | 317 | } |
58256307 KH |
318 | |
319 | mutex_unlock(&mbox_configured_lock); | |
340a614a HD |
320 | } |
321 | ||
58256307 | 322 | struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb) |
340a614a | 323 | { |
c0377320 KH |
324 | struct omap_mbox *_mbox, *mbox = NULL; |
325 | int i, ret; | |
340a614a | 326 | |
9c80c8cd FC |
327 | if (!mboxes) |
328 | return ERR_PTR(-EINVAL); | |
340a614a | 329 | |
c0377320 KH |
330 | for (i = 0; (_mbox = mboxes[i]); i++) { |
331 | if (!strcmp(_mbox->name, name)) { | |
332 | mbox = _mbox; | |
9c80c8cd | 333 | break; |
c0377320 KH |
334 | } |
335 | } | |
9c80c8cd FC |
336 | |
337 | if (!mbox) | |
338 | return ERR_PTR(-ENOENT); | |
340a614a | 339 | |
c7c158e5 | 340 | ret = omap_mbox_startup(mbox); |
340a614a HD |
341 | if (ret) |
342 | return ERR_PTR(-ENODEV); | |
343 | ||
58256307 KH |
344 | if (nb) |
345 | blocking_notifier_chain_register(&mbox->notifier, nb); | |
346 | ||
340a614a HD |
347 | return mbox; |
348 | } | |
349 | EXPORT_SYMBOL(omap_mbox_get); | |
350 | ||
58256307 | 351 | void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb) |
340a614a | 352 | { |
58256307 | 353 | blocking_notifier_chain_unregister(&mbox->notifier, nb); |
340a614a HD |
354 | omap_mbox_fini(mbox); |
355 | } | |
356 | EXPORT_SYMBOL(omap_mbox_put); | |
357 | ||
6b233985 HD |
358 | static struct class omap_mbox_class = { .name = "mbox", }; |
359 | ||
9c80c8cd | 360 | int omap_mbox_register(struct device *parent, struct omap_mbox **list) |
340a614a | 361 | { |
9c80c8cd FC |
362 | int ret; |
363 | int i; | |
340a614a | 364 | |
9c80c8cd FC |
365 | mboxes = list; |
366 | if (!mboxes) | |
340a614a | 367 | return -EINVAL; |
340a614a | 368 | |
9c80c8cd FC |
369 | for (i = 0; mboxes[i]; i++) { |
370 | struct omap_mbox *mbox = mboxes[i]; | |
371 | mbox->dev = device_create(&omap_mbox_class, | |
372 | parent, 0, mbox, "%s", mbox->name); | |
373 | if (IS_ERR(mbox->dev)) { | |
374 | ret = PTR_ERR(mbox->dev); | |
375 | goto err_out; | |
376 | } | |
58256307 KH |
377 | |
378 | BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier); | |
9c80c8cd | 379 | } |
f48cca87 HD |
380 | return 0; |
381 | ||
9c80c8cd FC |
382 | err_out: |
383 | while (i--) | |
384 | device_unregister(mboxes[i]->dev); | |
340a614a HD |
385 | return ret; |
386 | } | |
387 | EXPORT_SYMBOL(omap_mbox_register); | |
388 | ||
9c80c8cd | 389 | int omap_mbox_unregister(void) |
340a614a | 390 | { |
9c80c8cd | 391 | int i; |
340a614a | 392 | |
9c80c8cd FC |
393 | if (!mboxes) |
394 | return -EINVAL; | |
395 | ||
396 | for (i = 0; mboxes[i]; i++) | |
397 | device_unregister(mboxes[i]->dev); | |
398 | mboxes = NULL; | |
399 | return 0; | |
340a614a HD |
400 | } |
401 | EXPORT_SYMBOL(omap_mbox_unregister); | |
402 | ||
c7c158e5 | 403 | static int __init omap_mbox_init(void) |
340a614a | 404 | { |
6b233985 HD |
405 | int err; |
406 | ||
407 | err = class_register(&omap_mbox_class); | |
408 | if (err) | |
409 | return err; | |
410 | ||
b5bebe41 OBC |
411 | /* kfifo size sanity check: alignment and minimal size */ |
412 | mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t)); | |
ab66ac30 KH |
413 | mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size, |
414 | sizeof(mbox_msg_t)); | |
b5bebe41 | 415 | |
c7c158e5 | 416 | return 0; |
340a614a | 417 | } |
6b233985 | 418 | subsys_initcall(omap_mbox_init); |
340a614a | 419 | |
c7c158e5 | 420 | static void __exit omap_mbox_exit(void) |
340a614a | 421 | { |
6b233985 | 422 | class_unregister(&omap_mbox_class); |
340a614a | 423 | } |
c7c158e5 | 424 | module_exit(omap_mbox_exit); |
340a614a | 425 | |
f48cca87 HD |
426 | MODULE_LICENSE("GPL v2"); |
427 | MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging"); | |
f375325a OBC |
428 | MODULE_AUTHOR("Toshihiro Kobayashi"); |
429 | MODULE_AUTHOR("Hiroshi DOYU"); |